Audio disappears when I bounce

[jkoseattle]

I'm FINALLY freezing my tracks to audio for this project, woo hoo! All 30-ish tracks are freezing fine except one, which when frozen, simply goes blank - there is no audio clip at all. Playback bears this out as well. I can play the un-frozen track just fine, then I freeze, it goes through its paces, then the track is empty and silent. What's different about this one track from all the others?

Most tracks use EastWest Play synths, including the troubled one. The only thing I can think is different about this track is that it has more notes in it than any other, being the piano. This is true whether fast bounce is on or off.

[jkoseattle]

Moments after posting this, I discovered that there was in fact no audio from the Midi track. I re-loaded the synth and all is good. So as not to waste a perfectly good post here, the questions are now:

1) Is there a known cause for synths to just up and quit and need to be re-loaded again? Is this a thing or is something wrong that I can fix?

2) Is there a way to freeze all tracks in one operation?